Smoke emissions in jet engines are caused in part by particulates resulting from uncombusted portions of the jet fuel which result in part from impurities in the jet fuel. Combustor deposits in the jet engine are also a problem resulting from impurities in the fuel. In previous practice smoke emissions from jet engines were reduced by engine designing to maximize engine efficiency in combusting a high percentage of the jet fuel. Accordingly, it would be desirable to have jet fuel compositions and methods of making such compositions which lack the undesirable impurities and have reduced tendencies to cause smoke emissions.